Plans [was: Re: Gconf or GSettings? - leading to a wider question]

[Dirk Hohndel]

Linus Torvalds <torvalds at linux-foundation.org> writes:

> On Mon, Jan 21, 2013 at 6:57 AM, Dirk Hohndel <dirk at hohndel.org> wrote:
>>
>>
>> No, the maps.google.com implementation is correct - it doesn't "keep traveling" like the osmgpsmap implementation does.
>> But playing with it some more, what I did is indeed the behavior that I think makes more sense for us as we center the map around the dive site. So zooming in and out around the dive site is much more natural.
>
> That's only true in the single-dive map.
>
> In the "world" dive map (^M) the zoom behavior is very non-intuitive
> indeed. It's certainly better than the insane native OSM behavior, to
> the point of making the widget usable, but it would be good to figure
> out how to try to get the correct behavior.

I totally agree. I will claim that my hack is reasonably close to what
one would expect in "dive site" mode and is better than what we had in
"world" mode.

> Anyway, here's an example of how to do the iterative "zoom in at the
> right point even if osm doesn't have that interface".
>
> I'm not proud of it. It's a dirty disgusting hack, but it happens to
> work. It makes several assumptions about the map, most notable of them
> that the map translation is a pure cylindrical translation of
> latitude/longitude. That happens to be right for OSM (at least the
> form we use), so it seems to _work_, but it sure is hacky. It just
> does a "let's try to center the map at random locations and see how
> close we get to the target", where the "random locations" are just a
> binary rectangular search.
>
> The "binary rectangular search" is why it wouldn't work if OSM showed
> the world using some other map projection than the purely cylindrical
> one.
>
> It also wouldn't work correctly if OSM did the right thing and wrapped
> the world view - but again, OSM seems to do a pure rectangular mapping
> of lat/long to x/y.
>
> So this gets us the "correct" zooming behavior, but I want somebody
> else to look at the code. If you can stand it, commit it and add my
> sign-off. But I'll understand if anybody goes "that is too ugly to
> live, please just nuke it from space, that's the only way to make
> sure".

Well, the code doesn't make my eyes bleed and it is once again an
improvement compared to what we had - for the world view case. For the
dive site display I actually PREFER what I implemented. If I show the
map for the dive site and decide to zoom in or out... /I/ certainly want
this to zoom around the dive site, not around where my mouse happens to
be.

What do others think? What do you think, Linus? Should we use your code
for the world map and mine for the dive sites?

Oh, and while you are at it - have you looked at fixing that stupid edge
of the world problem where Fiji and Hawaii are not next to each other?
Can we simply paste a second map next to the existing one to make this
appear seemless (last time I flew to Australia there was no such edge -
we can check again next week...)

/D